Safecracker is a simple deduction game played with a standard deck of cards.
To setup, remove all 10s, jacks, queens, and kings from the deck. These cards will not be used. One card in each suit is removed. These cards make up the combination to the safe. The other cards are dealt out to the players. Some may get more than others.
The player with the fewest cards goes first. On a turn, a player asks about a possible combination, i.e. one card from each suit. All other players must announce how many of those cards they have and then show these cards to the active player. At any time, a player may say "stop!" and check to see if they have the right combination.
Optional rules to make the game easier allow calling a specific suit, in which case each player must show you one card of that suit, or, instead, a suit and a player, in which case that player must announce how many cards they have in that suit and then show you all of them.